The state that started a trend by making high school students tackle algebra II is now abandoning the policy in a move praised by school districts for affording more flexibility. But some policy experts are nervous because nearly 20 states have followed Texas’ lead in requiring the vigorous course.

Supporters say fewer course mandates give students more time to focus on vocational training for high-paying jobs that don’t necessarily require a college degree, such as at Toyota’s factory in San Antonio or oil and chemical giant BASF’s facilities on the Gulf Coast.

But critics say Texas — often watched for education policy — is watering down its standards. They note that test scores and graduation rates have improved since the tougher curriculum was adopted in 2006.

“Algebra II is a really, really powerful predictive value on whether kids go to college, but it goes on and on after that: more likely to have a full-time job, have a job with benefits, be healthier,” said Patte Barth, director of the Center for Public Education, a policy group affiliated with the National School Boards Association.

“It’s not just for the college bound.”

Sixteen other states, including Ohio, and the District of Columbia now require algebra II for most students, while Minnesota and Connecticut will do so soon. But Texas will join Florida — two of the country’s most populous states — in dropping the requirement when its Board of Education gives final approval to a curriculum overhaul next week.

That’s prompting some education groups to keep close tabs on other states because Texas’ classroom policy can have national implications. The state’s heavy reliance on tougher standardized testing under then-Gov. George W. Bush became the model for the federal No Child Left Behind law. Texas’ textbook market is so large that edits made for its classrooms can affect books sold nationwide.

“It’s funny that the banner-turning state would be backing off not so many years later,” said Jennifer Dounay Zinth, a policy analyst at Education Commission of the States.

She said her group is watching but hasn’t seen similar moves in other algebra II-requiring states so far.

Legislators overwhelmingly approved the change in May, even though Texas’ higher education commissioner, Raymond Paredes, said removing mandates for advanced math and science would leave more students ill-prepared for college and technical careers.

Florida scrapped a similar policy in April. But unlike Texas, Florida is among 45 states embracing national Common Core standards, meaning its students are expected to master some skills taught in algebra II.

Texas’ about-face came after strong pressure from Jobs for Texas, a coalition of 22 industry trade groups that argued the state’s curriculum was too rigid and no longer met the needs of the modern workforce.